Removed dst buffer delete responsibility from wxAnyValueType::CopyBuffer(), clarified documentation regarding it.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@62198 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/any.h

@@ -83,9 +83,14 @@ public:
     virtual void DeleteValue(wxAnyValueBuffer& buf) const = 0;
 
     /**
-        Implement this for buffer-to-buffer copy. src.m_ptr can
-        be expected to be NULL if value type of previously stored
-        data was different.
+        Implement this for buffer-to-buffer copy.
+
+        @param src
+            This is the source data buffer.
+
+        @param dst
+            This is the destination data buffer that is in either
+            uninitialized or freed state.
     */
     virtual void CopyBuffer(const wxAnyValueBuffer& src,
                             wxAnyValueBuffer& dst) const = 0;
@@ -259,13 +264,11 @@ public:
     virtual void DeleteValue(wxAnyValueBuffer& buf) const
     {
         Ops::DeleteValue(buf);
-        buf.m_ptr = NULL;  // This is important
     }
 
     virtual void CopyBuffer(const wxAnyValueBuffer& src,
                             wxAnyValueBuffer& dst) const
     {
-        Ops::DeleteValue(dst);
         Ops::SetValue(Ops::GetValue(src), dst);
     }
 
@@ -767,12 +770,15 @@ private:
     // Assignment functions
     void AssignAny(const wxAny& any)
     {
-        if ( !any.m_type->IsSameType(m_type) )
-        {
+        // Must delete value - CopyBuffer() never does that
         m_type->DeleteValue(m_buffer);
-            m_type = any.m_type;
-        }
-        m_type->CopyBuffer(any.m_buffer, m_buffer);
+
+        wxAnyValueType* newType = any.m_type;
+
+        if ( !newType->IsSameType(m_type) )
+            m_type = newType;
+
+        newType->CopyBuffer(any.m_buffer, m_buffer);
     }
 
     template<typename T>

interface/wx/any.h

@@ -321,6 +321,8 @@ union wxAnyValueBuffer
                                     wxAnyValueBuffer& dst) const
             {
                 // TODO: Copy value from one buffer to another.
+                //       dst is already uninitialized and does not
+                //       need to be freed.
             }
 
             virtual bool ConvertValue(const wxAnyValueBuffer& src,
@@ -394,9 +396,14 @@ public:
                               wxAnyValueBuffer& dst) const = 0;
 
     /**
-        Implement this for buffer-to-buffer copy. src.m_ptr can
-        be expected to be NULL if value type of previously stored
-        data was different.
+        Implement this for buffer-to-buffer copy.
+
+        @param src
+            This is the source data buffer.
+
+        @param dst
+            This is the destination data buffer that is in either
+            uninitialized or freed state.
     */
     virtual void CopyBuffer(const wxAnyValueBuffer& src,
                             wxAnyValueBuffer& dst) const = 0;

src/common/any.cpp

@@ -354,12 +354,12 @@ class wxAnyValueTypeImpl<wxAnyNullValue> : public wxAnyValueType
 {
     WX_DECLARE_ANY_VALUE_TYPE(wxAnyValueTypeImpl<wxAnyNullValue>)
 public:
+    // Dummy implementations
     virtual void DeleteValue(wxAnyValueBuffer& buf) const
     {
-        buf.m_ptr = NULL;  // This is important
+        wxUnusedVar(buf);
     }
 
-    // Dummy implementations
     virtual void CopyBuffer(const wxAnyValueBuffer& src,
                             wxAnyValueBuffer& dst) const
     {